Rastellum Carinatum Oyster Cretaceous Extinction Event Fossil Shell

Cretaceous Collector's Prize: Rastellum Oyster from Madagascar

Presenting a magnificent 61mm x 44mm Rastellum carinatum fossil from the paleontologically rich Mahajanga Province of Madagascar. This extinct oyster genus developed a highly distinctive morphology featuring prominent radiating ridges and an asymmetrical, curved form that resembles outstretched wings. During the Late Cretaceous Period (100-66 million years ago), Rastellum species dominated certain shallow marine habitats, using their specialized shells to stabilize themselves in shifting sediments while filtering microscopic organisms from the water. These remarkable creatures perished during the K-Pg extinction event 66 million years ago, when the combined effects of asteroid impact, massive volcanism, and climate disruption devastated marine ecosystems globally. This specimen fossilized through diagenesis, where minerals from surrounding sediments gradually permeated the shell, replacing organic material with durable stone while maintaining the original structure.

The presence of Rastellum fossils helps scientists reconstruct ancient ocean conditions, understand extinction patterns, and identify evolutionary adaptations in marine invertebrates.

Enhance your fossil collection with this extraordinary Cretaceous specimen today!